The Carbon Farming Initiative and Agricultural Emissions

This presentation was prepared by the University of Melbourne for the Regional Landcare Facilitator training funded through the Australian Government’s Carbon Farming Initiative Communications Program

PART 1: INTRODUCTION TO THE SCIENCE OF AGRICULTURAL EMISSIONS AND SINKS

This presentation provides a basic understanding of the soil, plant and animal carbon and nitrogen cycles

The Carbon cycle

http://www.davidsuzuki.org/files/CCcarboncycle.GIF

C-stocks in Pg (Gt), C-fluxes in Pg yr -1 ; Pg = 10 15 g = 1 Gt (gigatonne) • Large carbon pools, relatively small fluxes between pools • More carbon emissions than carbon uptake  fossil fuel emissions • Increase carbon sinks – increase terrestrial plant or soil sinks

Global forest distribution

www.fao.org/forestry

Sources of global CO 2 emissions

10 8 6 4 2 Fossil fuel Land use change 1960 1970 1980 1990 2000 2010 Le Quéré et al. 2009, Nature-Geoscience; Data: CDIAC, FAO, Woods Hole Research Center 2009 12% of total anthropogenic emissions Slide courtesy of J. Canadell, Global Carbon Project

Carbon stocks and sequestration Carbon stock/pools

How much C at one point in time

Aboveground biomass

Leaves, stem, branches

Litter & coarse woody debris Below ground biomass

Coarse roots, fine roots, microbes

Soil carbon

Stable and labile fractions

Carbon sequestration

Change of C stock over time

NPP

Net primary productivity

14 12 NPP blowground Forests produce most of the terrestrial carbon 10 8 6 4 2 Tropical forest are the most productive Crops produce mainly aboveground NPP  consequences for soil C 0 -2 0.5 2.6 8.1 21.9 14.9 7.0 3.5 4.1 NPP Pg C yr -1 Tundr a Boreal For es t per at e For Tr es t opic Tem al Fores Tr opic t al sav anna p gr as sland Tem D es er ts C rops Saugier (2001) IN: Terrestrial Global Productivity

The Carbon cycle

• Human activity greatly influences the global C cycle • The sink capacity of natural CO 2 sinks is decreasing, leading to increased atmospheric CO 2 • Forest ecosystems are the greatest carbon sink in the terrestrial biosphere • Globally, soils store more C than biomass • The capacity of an ecosystem to store C is determined by the balance of C uptake (photosynthesis) and C loss (respiration)